Filter

This spell creates an invisible bubble of protection around the recipient’s body that filters out all noxious and toxic elements in the air.

(Tome and Blood: A Guidebook to Wizards and Sorcerers)  
Originally posted on D&D tools

Abjuration

Level: Cleric 2, Druid 2, Sorcerer, Wizard 2,
Components: V, S, M, DF,
Casting Time: 1 action
Range: Touch
Target: Creature touched
Duration: 10 minutes/level
Saving Throw: Will negates (harmless)
Spell Resistance: Yes

The warded creature takes no damage and no penalties from inhaled natural or alchemical poisons. It is likewise protected against magical poisons created by spells of 4th level or lower (such as stinking cloud) cast by creatures of 8 or fewer Hit Dice. Against more powerful affects, the creature receives a +2 circumstance modifier on any saving throw allowed.

Arcane Material Component: A strand of spider web and a scrap of cotton cloth.